Maleic anhydride copolymers have been previously investigated as scale inhibiting agents in feed waters of various types of heat exchangers. U.S. Pat. No. 3,650,970 discloses the use of alkali metal or ammonium salts of a polymer formed by esterifying styrene-maleic anhydride copolymers with capped polyethylene glycol as calcium sulfate scale inhibitors. U.S. Pat. No. 3,715,307 to Johnson et al discloses the use of maleic anhydride vinyl acetate copolymers to reduce maintenance problems associated with the use of water and heat transfer equipment. U.S. Pat. Nos. 3,723,956, 3,617,557, 3,289,734, and 3,775,264 disclose the use of other copolymers as scale inhibitors in various types of heat exchangers.
The copolymers of maleic anhydride and furan covered in the instant application are described in the "Journal of Macromolecular Science-Chemistry", Vol. A4 (1), pages 52 to 54.
These copolymers are described in U.S. Pat. No. 3,850,832 for use as sequestering agents in washing, rinsing and cleaning compositions.